Validity of Health Assessment Questionnaire Disability Index (HAQDI) for Assessing Disease Activity in Iraqi Patients with Active Rheumatoid Arthritis

Objective: Rheumatoid arthritis is a common autoimmune disease associated with many complications like joint damage, disability and even death. It requires early and aggressive treatment with regular follow up to ensure safety and effectiveness of treatment for the patients. Disease activity score of 28 joints (DAS28) and simplified disease activity index (SDAI) are common tools that used to assess disease activity, whereas health assessment questionnaire disability index (HAQDI) is a patient reported tool for assessing patient functional ability. This study aimed to evaluate the effectiveness of HAQDI score for monitoring disease activity and response to therapy in Iraqi patients with active rheumatoid arthritis. Methods: A cross-sectional study was conducted in Baghdad Teaching Hospital, Rheumatology out patient Unit from August 2011 to May 2012. A total of 95 patients (21 males and 74 females) with active RA were involved in this study. Disease activity was measured by DAS28 and the SDAI whereas functional status of the patients was measured using HAQDI score. Results: There was a significant positive correlation of HAQDI score with clinical parameters like swelling joint count (SJC), tender joint count (TJC), visual analogue scale (VAS), physician global assessment (EGA) and morning stiffness. Additionally HAQDI was significantly correlated with disease activity scores DAS28 and SDAI. Furthermore it correlated with inflammatory markers ESR and CRP. HAQDI score was better correlated with clinical parameters in patients with high disease activity than those with moderate activity. Conclusion: HAQDI score is a valid and useful tool to monitor disease activity and response to treatment in Iraqi patients with highly active RA.